The analgesic is one of the most commonly used drugs in the clinic. However, potent analgesics such as morphine and dulantin have strong potential for inducing dependence, which may cause addiction and tolerance while used for a long time; although non-narcotic analgesics have no potential for inducing dependence, the analgesic effect thereof are weak and insufficient to relieve severe pain in patients with cancer, trauma and surgery. Therefore, it is clinically necessary to provide a novel effective and safe analgesic.
Buprenorphine is the most commonly used analgesic and drug addiction eliminating medicine in the clinic; ADP2 is a buprenorphine analog that shows significantly higher analgesic activity and analgesic potency than buprenorphine (Master's thesis: Synthesis of buprenorphine analogs. 1999.6, graduate student: Wu Bo; instructor: Zhong Bohua). However, both buprenorphine and ADP2 have certain addictive properties, and are only effective for injection administration, which limits their clinical application. Continuously administration of buprenorphine in the clinic brings side effects of constipation.

The object of the present invention is to provide novel buprenorphine analogs that are orally effective and have low potential for inducing dependence.